Leaders of rival Palestinian groups Hamas and Fatah headed to Saudi Arabia on Tuesday to hold talks aimed at ending bloody factional warfare and forming a unity government.

Previous efforts to stem the bloodshed and find common political ground have resulted in short-lived ceasefires. More than 80 Palestinians have been killed in the internal fighting since December.

Palestinian President Mahmoud Abbas warned that failure in Mecca "would mean the deterioration of the internal situation and igniting civil war," the Lebanese newspaper Al-Akhbar quoted him as saying.

"The word 'failure' is forbidden," he was quoted as saying Tuesday before leaving for talks with Hamas leader Khaled Mashaal.

Mashaal and Abbas arrived in Jiddah, where they were to meet Saudi King Abdullah, Crown Prince Sultan and Foreign Minister Prince Saud Al-Faisal. The city is less than an hour's drive from Mecca.

Even as Palestinian Prime Minister Ismail Haniyeh left the Gaza Strip for the talks on Tuesday, Hamas and Fatah security officials exchanged gunfire for 10 minutes at the Gaza-Egypt crossing terminal. No casualties were reported.

Haniyeh told reporters that his Hamas delegation was determined to reach agreement.

"Nobody wants the battling to continue," he said after crossing into Egypt. "The only beneficiary is Israel."

In recent months, Egypt, Syria and Qatar have all tried and failed to end the violent power struggle.

Unity talks deadlocked

Abdullah made clear he hoped the sacred setting would have an influence when he issued a statement to the Palestinian community in Saudi Arabia.

"I hope that the Palestinian brothers hear your demand, and that they will not leave the sacred land without a commitment before God to stop fighting and bloodshed," the king said.

Kadoura Fares, a former Fatah cabinet minister who met Mashaal last week, told Israel's Army Radio that Fatah and Hamas had overcome almost all the obstacles to forming a coalition government during talks in recent weeks.

The rival factions have been deadlocked since Hamas won the Palestinian elections in January 2006 and took control of the cabinet and legislature.

Western nations, including Canada, promptly imposed a financial blockade on the Palestinian government because of Hamas's refusal to renounce violence and recognize Israel and previous agreements signed between the Palestine Liberation Organization and Israel.

Abbas, a moderate who was elected separately in 2005, started negotiating with Hamas last fall in the hope that a coalition government would enable the West to lift the boycott and allow the return of aid money. By then, thousands of Palestinians had gone unpaid for months.

With files from the Associated Press